diff --git a/AgileConfig.Server.Common/Encrypt.cs b/AgileConfig.Server.Common/Encrypt.cs
new file mode 100644
index 00000000..6690345f
--- /dev/null
+++ b/AgileConfig.Server.Common/Encrypt.cs
@@ -0,0 +1,17 @@
+using System;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace AgileConfig.Server.Common
+{
+    public static class Encrypt
+    {
+        private static readonly MD5 Md5Instance = MD5.Create();
+        public static string Md5(string txt)
+        {
+            var inputBytes = Encoding.ASCII.GetBytes(txt);
+            var hashBytes = Md5Instance.ComputeHash(inputBytes);
+            return Convert.ToHexString(hashBytes);
+        }
+    }
+}
diff --git a/AgileConfig.Server.Common/encrypt.cs b/AgileConfig.Server.Common/encrypt.cs
deleted file mode 100644
index 9745ccb9..00000000
--- a/AgileConfig.Server.Common/encrypt.cs
+++ /dev/null
@@ -1,27 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Security.Cryptography;
-using System.Text;
-
-namespace AgileConfig.Server.Common
-{
-    public class Encrypt
-    {
-        public static string Md5(string txt)
-        {
-            using (var md5 = MD5.Create())
-            {
-                var inputBytes = Encoding.ASCII.GetBytes(txt);
-                var hashBytes = md5.ComputeHash(inputBytes);
-
-                // Convert the byte array to hexadecimal string
-                var sb = new StringBuilder();
-                for (var i = 0; i < hashBytes.Length; i++)
-                {
-                    sb.Append(hashBytes[i].ToString("X2"));
-                }
-                return sb.ToString();
-            }
-        }
-    }
-}